1. Field of the Invention
The present invention relates to a measurement device used for both optical measurement and mass spectrometry, a measurement apparatus that performs both optical measurement and mass spectrometry using the measurement device, and a measurement method.
2. Description of the Related Art
Hitherto, as an analysis method used for the identification of a substance, and the like, there has been known a mass spectrometry method in which an analysis target substance which adheres to the surface of a substrate is desorbed from the surface of the substrate and is ionized, thereby identifying the substance on the basis of a ratio of the mass of the substance to an electric charge (see JP5069497B, JP2012-117245A, and JP2008-107209A). For example, in time-of-flight mass spectroscopy (TOF-MS), an ionized analysis target substance is flown by a predetermined distance between high voltage electrodes, and the mass of the substance is analyzed on the basis of a flight time thereof.
A method of desorbing and ionizing an analysis target substance in such a mass spectrometry method includes a laser desorption/ionization method utilizing laser irradiation, and a surface-enhanced laser desorption/ionization (SELDI) method has been proposed as the laser desorption/ionization method.
The SELDI method is a method of capturing an analysis target substance, having a specific property, which is present in a specimen, on a chip using a chemical functional group and molecules which are fixed to the surface of the chip, refining the analysis target substance, and then desorbing and ionizing the captured analysis target substance by performing laser irradiation.
On the other hand, similarly to the above-mentioned mass spectrometry of a substance, a Raman spectroscopy method is known as a method of performing the identification of a substance. The Raman spectroscopy method is a method of obtaining a spectrum of Raman scattered light (Raman spectrum) by separating scattered light obtained by irradiating a substance with single wavelength light, and can include analyzing the spectrum for the identification of the substance.
The above-mentioned Raman spectroscopy method includes so-called surface enhanced Raman (SERS) using an optical electric field which is enhanced by localized plasmon resonance in order to enhance feeble Raman scattered light.
This method uses a principle in which when a metal body, particularly, a metal body having nano-order irregularities in the surface thereof is irradiated with light in a state where the metal body is brought into contact with a substance, an optical electric field is enhanced by localized plasmon resonance, and the intensity of Raman scattered light of a specimen coming into contact with the surface of the metal body is enhanced.